Depicting the Spatial Distribution of Proteins in Human Tumor Tissue Combining SELDI and MALDI Imaging and Immunohistochemistry

Carcinoma tissue consists of not only tumor cells but also fibroblasts, endothelial cells or vascular structures, and inflammatory cells forming the supportive tumor stroma. Therefore, the spatial distribution of proteins that promote growth and proliferation in these complex functional units is of high interest. Matrix-assisted laser desorption/ionization imaging mass spectrometry is a newly developed technique that generates spatially resolved profiles of protein signals directly from thin tissue sections. Surface-enhanced laser desorption/ionization mass spectrometry (MS)combined with tissue microdissection allows analysis of defined parts of the tissue with a higher sensitivity and a broader mass range. Nevertheless, both MS-based techniques have a limited spatial resolution. IHC is a technique that allows a resolution down to the subcellular level. However, the detection and measurement of a specific protein expression level is possible only by semiquantitative methods. Moreover, prior knowledge about the identity of the proteins of interest is necessary. In this study, we combined all three techniques to gain highest spatial resolution, sensitivity, and quantitative information. We used frozen tissue from head and neck tumors and chose two exemplary proteins (HNP1–3 and S100A8) to highlight the advantages and disadvantages of each technique. It could be shown that the combination of these three techniques results in congruent but also synergetic data. (J Histochem Cytochem 58:929–937, 2010)     

DNA-polymorphic patterns linked to the β-globin genes in German families affected with hemoglobinopathies and thalassemias: a comparison to other ethnic groups

Summary DNA haplotype constellations of the β-globin gene cluster have been analyzed in German families with hemoglobinopathies (Hb Freiburg, Hb K?ln, Hb Presbyterian) and β-thalassemias. The polymorphis patterns obtained were compared to those found in families from Greece, Italy, and Turkey affected by β-thalassemia syndromes. With the combined analysis of seven restriction site polymorphisms a DNA-diagnostic prediction for additional offspring could be made with an overall frequency of 75% in the four ethnic groups.     

The effect of centrifugal accelerations on the polarity of statocytes and on the graviperception of cress roots

The structural polarity of statocytes of Lepidium sativum L. is converted to a physical stratification by a root-tip-directed centrifugal acceleration. Sedimentation of amyloplasts and nucleus to the centrifugal (distal) cell pole and the lateral displacement of the distal endoplasmic reticulum (ER) complex occur after centrifugation for 20 min at an acceleration of 50 g. With higher doses (20 min, 100-2,000 g), smaller organelles become increasingly displaced. From the centrifugal to the centripetal cell pole, the following stratification is observed: 1) amyloplasts with mitochondria; 2) nucleus with mitochondria and a few dictyosomes, as well as laterally located ER; 3) dictyosomes with a few mitochondria; 4) vacuoles; and 5) lipid droplets. Within the first 7.5 min, after the roots have been returned to 1 g, the original arrangement of the amyloplasts sedimented on the underlying ER complex is reestablished in 66% of the statocytes. When roots previously centrifuged in an apical direction are exposed in a horizontal position to 1 g, the latent period of the graviresponse is increased by 7.5 min relative to the non-centrifuged controls. The kinetics of the response are identical to the controls. Roots centrifuged first in an apical direction and then for 2 h in a lateral direction (1,000 g) have statocytes with a physical stratification perpendicular to the root axis. A gravitropic curvature does not take place during the lateral centrifugation. These results support the hypothesis that the distal ER complex is necessary and sufficient for graviperception.     

Modulation of locomotor activity by substance P in rats

The effects of intraperitoneally or intracerebrally (DA A-10 area) administered substance P (SP) on locomotor activity of rats were studied in an exact 12-h light/12-h dark cycle changing from dark to light at 6 a.m. SP was administered either at 11 a.m. (light phase, minimal locomotor activity) or at 7 p.m. (dark phase, maximal locomotor activity). The effects of 12.5 micrograms/kg SP intracerebral and 125 micrograms/kg SP intraperitoneal were very similar. In the light phase SP produces excitation but inhibition of locomotion in darkness. Hence, the effect of SP depends on the internal mechanisms controlling motor activity and tends to level off the spontaneous circadian oscillation. We found a long lasting SP effect during both the light and dark period. The present experiments led us to the conclusion that SP has a levelling effect on locomotor activity. Probably this effect might be explained as SP's action on the dopaminergic pathway or dopamine metabolism, because the dopamine content in neurons also has a circadian rhythm.     

Deoxyribonucleic Acid of Adeno-associated Satellite Virus

Staining patterns suggest that in the adeno-associated satellite virion there exist quasi single-stranded regions which are renatured after extraction to exhibit double strandedness.     

Substance P inhibition of the activity of the angiotensin-converting enzyme from human blood serum

Substance "P" (SP) and its derivatives inhibited activity of angiotensin-converting enzyme (ACE) in human blood serum, I50 for SP was 31 microM. The same results were obtained for N-terminal fragments of the SP molecule: Arg-Pro-Lys-Pro and Lys-Pro. The C-terminal heptapeptide and the dipeptide Arg-Pro negligibly inhibited ACE activity. A possible significance of the interaction between SP and ACE in the regulation of the microhemodynamics is discussed.     

Analysis of the Albino-Locus Region of the Mouse. I. Origin and Viability

Numerous specific-locus experiments designed to test the mutagenic effect of external radiation have yielded, in over 3,600,000 animals observed, altogether 119 presumed mutations involving the c locus. Of these, 55 were viable and albino (cav), 13 were viable and of various intermediate pigment types (cxv), four were subvital (cas and cxs), seven were neonatally lethal albinos (cal), 28 prenatally lethal albinos (cal); 12 died untested. All of the prenatally lethal and at least one of the neonatally lethal c-locus mutations (cal classes) are probably deficiencies that we have analyzed extensively in other experiments. Since absence of the locus mimics albino in phenotype, the intermediates (cxv and cxs groups) probably resulted from intragenic changes. The class of viable albino mutants (cav) might include, in addition to intragenic changes, some extremely small deficiencies. --The effects on viability of c-locus lethals (cal's) in heterozygous condition are not drastic enough to be perceived in stocks of mixed genetic background except in the case of the two longest known deficiencies and a few others. --Analysis of the relation between radiation treatment and type of c-locus mutants obtained shows that the relative frequency of viable mutations, for each germ-cell type, is greater for low-LET than for neutron irradiation; however, the difference for any individual cell type is not significant. The majority (66.7%) of mutations derived from X- or gamma-ray irradiated spermatogonia are viable, and the proportion of "intermediates" among these viables is similar to that among presumed spontaneous c-locus mutations. No significant dose-rate effect on the proportion of lethals could be demonstrated within the set of mutants induced by low-LET irradiation of spermatogonia. Although sets from other germ-cell stages are too small for statistical tests, the results for oocytes are similar, as far as they go. Furthermore, most of the c-locus mutations induced in spermatogonia, even by high-dose-rate X-ray or gamma irradiation, are of a type most likely to result from single-tract events (62% cxv, cxs, and cav; plus 16% presumed deficiencies not involving the closest marker). These results support the view that most of the reduction in mutation frequency at low dose rates is not due to a change in relative proportion of two-track and one-track ionizing events.     

Studies on the mechanism of action of peptide attacking smooth muscle. II. Differentiation of biologic activity of tachykinins in affinity and intrinsic efficacy]

Under the condition of receptor blockade produced by continuous presence of an agonist in the organ bath, it was attempted to determine the dissociation constants for C-terminal partial sequences of the substance P at an isolated guinea pig ileum, by analogy with the method involving irreversible antagonists, and to compare them with the biological activity at the guinea pig ileum and the rat colon (ED50 values). Differentiation of the biological activity at the guinea pig ileum into affinity and "intrinsic efficacy" allows one to explain quantitative differences in determining the biological value on both isolated organs, and to reveal the contribution of the individual amino acids to affinity and "intrinsic efficacy".