Age-related accumulation of congophilic fibrillar inclusions in endocrine cells

Summary Intracellular fibrillar congophilic inclusions are well known as neurofibrillary tangles in neurons and as Biondi bodies in choroid plexus epithelial cells. Recently similar amyloid-like inclusions in adrenal cortical cells were described (Eriksson and Westermark 1990). This study on 150 adrenal glands confirms these observations. In our material the age-related accumulation of congophilic inclusions starts earlier (in the sixth decade) and reaches a higher incidence (42.7%). We found similar intracellular inclusions in other endocrine organs, for example in the anterior lobe of the pituitary, in the cells of parathyroid glands and in Sertoli cells. The age-related incidence of these fibrillar inclusions in the pituitary was 68%; the co-incidence with interstitial amyloid deposits was 49.5%. Thus the intracellular accumulation of congophilic fibrils in old age is a widespread phenomenon and occurs not only in neurons but also in endocrine cells (adrenal, pituitary and parathyroid glands) and in active secretory cells (choroid plexus and Sertoli cells).     

Cytogenetic analysis of the Asian Plethodontid salamander, Karsenia koreana: Evidence for karyotypic conservation, chromosome repatterning, and genome size evolution

A cytogenetic analysis, including the karyotype, C-bands, silver-stained nucleolus organizer regions and genome size, was performed on the recently discovered species, Karsenia koreana, the first plethodontid salamander from Asia. The karyotype consists of 14 pairs of bi-armed chromosomes, with no evidence of heteromorphic sex chromosomes. C-banding reveals a concentration of heterochromatin at the centromeres as well as at interstitial locations. The smallest chromosome (pair number 14) has symmetrical interstitial C-bands in each arm, resembling chromosome no. 14 of North American species of its sister group taxon, supergenus Hydromantes. Acomparative analysis of C-band heterochromatin and silver-stained nucleolus organizer regions of Karsenia and other plethodontid genera reveals that chromosomal evolution may have featured chromosome 'repatterning' within the context of conserved chromosome number and shape in this clade. Genome size is correlated with geographic distribution in plethodontids and appears to have important phenotypic correlates as well. The genome size of Karsenia is relatively large, and resembles that of the geographically closest plethodontids from western North America, especially species of the genus Hydromantes. The biological significance of these cytogenetic characteristics of plethodontid salamanders is discussed within an evolutionary context.     

Evolution of the neuropeptide Y receptor family: gene and chromosome duplications deduced from the cloning and mapping of the five receptor subtype genes in pig

Neuropeptide Y (NPY) receptors mediate a variety of physiological responses including feeding and vasoconstriction. To investigate the evolutionary events that have generated this receptor family, we have sequenced and determined the chromosomal localizations of all five presently known mammalian NPY receptor subtype genes in the domestic pig, Sus scrofa (SSC). The orthologs of the Y(1) and Y(2) subtypes display high amino acid sequence identities between pig, human, and mouse (92%-94%), whereas the Y(4), Y(5), and y(6) subtypes display lower identities (76%-87%). The lower identity of Y(5) is due to high sequence divergence in the large third intracellular loop. The NPY1R, NPY2R, and NPY5R receptor genes were localized to SSC8, the NPY4R to SSC14, and NPY6R to SSC2. Our comparisons strongly suggest that the tight cluster of NPY1R, NPY2R, and NPY5R on human chromosome 4 (HSA4) represents the ancestral configuration, whereas the porcine cluster has been split by two inversions on SSC8. These 3 genes, along with adjacent genes from 14 other gene families, form a cluster on HSA4 with extensive similarities to a cluster on HSA5, where NPY6R and >13 other paralogs reside, as well as another large cluster on HSA10 that includes NPY4R. Thus, these gene families have expanded through large-scale duplications. The sequence comparisons show that the NPY receptor triplet NPY1R-NPY2R-NPY5R existed before these large-scale duplications.     

Freezing induces artificial cleavage of apoptosis-related proteins in human bone marrow cells

The aim of this study was to investigate whether freeze-thawing of freshly isolated human mononuclear bone marrow cells (MNC) influences the integrity of apoptosis-related proteins as determined by immunoblot analyses. Our results show that bone marrow is more sensitive to this process than either myelomonocytoid leukemic P39 or Jurkat T-lymphocyte cell lines. Specifically, bone marrow cells displayed a high level of intrinsic proteolytic activity in response to a single freeze-thaw cycle, which led to the cleavage of various proteins involved in apoptosis cell signaling. This effect was completely blocked by the inclusion of broad-spectrum protease inhibitors in the freezing medium and subsequently thawing the cells on ice. Since differences in the freezing conditions (-80 degrees C vs. liquid nitrogen) did not alter the proteins of interest, we suggest that the thawing process is the critical point when proteolytic enzyme activity is elevated.     

Comparative dosimetry of diode and diamond detectors in electron beams for intraoperative radiation therapy

The aim of the present study is to examine the validity of using silicon semiconductor detectors in degraded electron beams with a broad energy spectrum and a wide angular distribution. A comparison is made with diamond detector measurements, which is the dosimeter considered to give the best results provided that dose rate effects are corrected for. Two-dimensional relative absorbed dose distributions in electron beams (6-20 MeV) for intraoperative radiation therapy (IORT) are measured in a water phantom. To quantify deviations between the detectors, a dose comparison tool that simultaneously examines the dose difference and distance to agreement (DTA) is used to evaluate the results in low- and high-dose gradient regions, respectively. Uncertainties of the experimental measurement setup (+/- 1% and +/- 0.5 mm) are taken into account by calculating a composite distribution that fails this dose-difference and DTA acceptance limit. Thus, the resulting area of disagreement should be related to differences in detector performance. The dose distributions obtained with the diode are generally in very good agreement with diamond detector measurements. The buildup region and the dose falloff region show good agreement with increasing electron energy, while the region outside the radiation field close to the water surface shows an increased difference with energy. The small discrepancies in the composite distributions are due to several factors: (a) variation of the silicon-to-water collision stopping-power ratio with electron energy, (b) a more pronounced directional dependence for diodes than for diamonds, and (c) variation of the electron fluence perturbation correction factor with depth. For all investigated treatment cones and energies, the deviation is within dose-difference and DTA acceptance criteria of +/- 3% and +/- 1 mm, respectively. Therefore, p-type silicon diodes are well suited, in the sense that they give results in close agreement with diamond detectors, for practical measurements of relative absorbed dose distributions in degraded electron beams used for IORT.     

Effect of increased distal sodium delivery on organic osmolytes and cell electrolytes in the renal outer medulla

Sodium absorption in distal tubule segments was stimulated by increasing the distal delivery via infusion of hypertonic saline. In these animals, and in control rats, electrolyte concentrations in thick ascending limb cells, light and dark cells of the collecting duct in the outer and inner stripe of the outer medulla and in cells of the proximal straight tubule (outer stripe only) were studied. The measurements were performed by electron microprobe analysis of freeze-dried cryosections of the outer medulla. In addition, organic osmolytes (glycerophosphorylcholine, betaine and myo-inositol) were measured by high performance liquid chromatography in cortex and outer medulla. Augmented delivery of sodium chloride to the distal tubule was associated with increased sodium concentrations of thick ascending limb cells both in the outer and inner stripe and of medullary collecting duct light and dark cells in the outer stripe. While the sum of organic osmolyte concentrations was 28% higher in the outer medulla of the salt-loaded animals compared with controls, this value was unchanged in the renal cortex. These findings indicate that the primary event underlying stimulation of sodium absorption along the thick ascending limb during increased distal sodium delivery is enhanced entry of sodium across the apical cell membrane. This would be expected to lead to higher cell sodium concentrations and stimulation of basolateral active Na-K-exchange. The enhanced transport activity of outer medullary tubules may be associated with increased interstitial tonicities and intracellular retention of organic osmolytes.     

Levels of immunoglobulin G antibodies against defined epitopes of the L1 and L2 capsid proteins of human papillomavirus type 6 are elevated in men with a history of condylomata acuminata.

Sera from 159 men attending the sexually transmitted disease clinic at Karolinska Hospital, Stockholm, Sweden, were analyzed for the presence of immunoglobulin A (IgA) and IgG antibodies to a panel of synthetic peptides derived from the E2, L1, and L2 regions of the human papillomavirus types 1 (HPV 1), 6, 8, 11, 16, 18, 31, and 33. The study subjects were divided into three groups: (i) asymptomatic men with no history of genital warts who served as controls, (ii) men with visible condylomata, and (iii) men who had previously been afflicted with condylomata. There were no significant differences in antibody titers for any of the HPV 6- or 11-derived peptides among patients with current condylomata and the controls. For the peptide from L1 of HPV 6, there was an increase in the IgG titers among men with previous condylomata compared with the titers for the controls (52% versus 27% seropositivity; P less than 0.05). Also, for the peptide from L2 of HPV 6, there was an increase in the IgG titers among men who had been afflicted with condylomata previously (P less than 0.05). Increased IgA antibody titers against an HPV 16-derived peptide and an HPV 18-derived peptide were also detected. For the peptides from L1 and L2 of HPV 6, the study was extended to an additional group of 127 males attending the sexually transmitted disease clinic at Huddinge Hospital in southern Stockholm. Again, significantly increased antibody levels were detected only for IgG and only among asymptomatic men with a history of condylomata (P < 0.01 for the L1 peptide and P < 0.05 for the L2 peptide). The results suggest that the IgG response against the late proteins of HPV 6 reflects mainly previous exposure to the virus rather than ongoing viral disease.     

High diversity of ankA sequences of Anaplasma phagocytophilum among Ixodes ricinus ticks in Germany

In Germany humans with acute granulocytic ehrlichiosis have not yet been described. Here, we characterized three different genes of Anaplasma phagocytophilum strains infecting German Ixodes ricinus ticks in order to test whether they differ from strains in other European countries and the United States. A total of 1,022 I. ricinus ticks were investigated for infection with A. phagocytophilum by nested PCR and sequence analysis. Forty-two (4.1%) ticks were infected. For all positive ticks, parts of the 16S rRNA and groESL genes were sequenced. The complete coding sequence of the ankA gene could be determined in 24 samples. The 16S rRNA and groESL gene sequences were as much as 100% identical to known sequences. Fifteen ankA sequences were >/=99.37% identical to sequences derived from humans with granulocytic ehrlichiosis in Europe and from a horse with granulocytic ehrlichiosis in Germany. Thus, German I. ricinus ticks most likely harbor A. phagocytophilum strains that can cause disease in humans. Nine additional sequences were clearly different from known ankA sequences. Because these newly described sequences have never been obtained from diseased humans or animals, their biological significance is currently unknown. Based on this unexpected sequence heterogeneity, we propose to use the ankA gene for further phylogenetic analyses of A. phagocytophilum and to investigate the biology and pathogenicity of strains that differ in the ankA gene.     

Serum and urine light chain levels in benign monoclonal gammapathies, multiple myeloma and Waldenström''s macroglobulinaemia

Immunochemical quantitative determinations of both serum and urine free light chains were carried out in seventy-five subjects with a serum M-component.

Diagnoses were benign monoclonal gammapathy (BMG) in thirty-four cases, multiple myeloma (MM) in thirty-one and Waldenström's macroglobulinaemia (WM) in ten. The single radial immunodiffusion test was used throughout, employing a special rabbit anti-Bence Jones antiserum, made specific for hidden antigenic sites of light chains by suitable absorptions. The smallest amount of free light chains which could be detected by this method was 0·02 mg/ml for both κ and λ chains.

In MM 84% of sera and 87% of urine revealed detectable amounts of Bence Jones protein, whereas in WM the corresponding figures were 80% for both sera and urines. The values ranged considerably from case to case, and tended to be higher in the urines. In BMG a definitely lower incidence of free light chains was recorded (in the sera: 35·2%; in the urines: 41·1%), and the levels were restricted to a much narrower range.

The significance of these findings is briefly discussed.